NanoLect4 - Protein Channels Nature's Quintessential...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Protein Channels – Nature’s Quintessential Bio/Nano Devices Cell Membrane - Impermeable lipid bilayer Membrane-Bound Protein Channel Key Functions of Protein Channels: Transport specific molecules and ions across the cell membrane. Electrical signaling (e.g., voltage-gating ) in nerve and muscle cells.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Selective Transport – The Channel is a Nanotube with a Binding Site that Selects the Molecule/Ion to be Transported Abramson, et al. Science 2003 , 301 , 610. Model of Lactose Permease from E. Coli Bilayer Membrane Hydrophilic cavity containing sugar binding site Bound sugar Center for Research at the Bio/Nano Interface
Background image of page 2
Electrical Signaling – Ion Channels Open and Close in Response to Specific Chemical or Electrical Signals Lipid bilayer membrane Out In Outer helix Pore helix Model of a Voltage-Gated Potassium Channel From B. Hille, “Ion Channels of Excitable Membranes,” Vol 3.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Current-Voltage Curve for a Voltage-Gated Potassium Channel Transmembrane Potential (mV) Transmembrane Current (pA) Open or “On” State Y. Jiang, A. Lee, J. Chen, M. Cadene, B.T. Chait, R. MacKinnon, Nature 417 (2002) 515. Closed or “Off” State
Background image of page 4
Artificial Channels – Why would we want to Mimic The Selective-Transport and Open/Close-Gating Functions of Nature’s Channels? Selective-Transport – Synthetic membranes containing chemically selective artificial channels could be used to do bioseparations – e.g. pharmaceutical, genomic, proteomic. Open/Close – This gating function can be used as a signal transduction scheme in biosensor platforms. But how does one make an artificial channel ?
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Template synthesis provides a route for preparing nanotubes of any desired dimensions , any desired shape and composed of any desired material , to yield nanotubes having any desired properties . Template-Synthesized Nanotubes June 11, 2001 cover of Chemical and Engineering News .
Background image of page 6
Bilayer Membrane Hydrophilic cavity containing sugar binding site Bound sugar Mimicking the Selective Transport Function Like natures channels, we incorporate biochemical molecular-recognition agents into our nanotubes so that they selectively recognize, bind and transport specific molecules
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Schematic of a Nanotube Membrane with a Molecular-Recognition Agent, or “Transporter,” Attached to the Nanotube Walls X Molecular-Recognition Agent Facilitated Transport - Under Optimal Conditions, the Bound Molecule is Transported Faster than Molecules that do not Bind to the Molecular Recognition Agent
Background image of page 8
Some of the Chemical and Biochemical Molecular- Recognition Agents (Transporters) We Have Incorporated into Our Nanotube Membranes Type of Nanotube Transporter Membrane is Selective for Reference Polymer Apoenzyme Substrate of Enzyme Nature , 1997 , 388 , 758 Gold CH 3 -(CH 2 ) 15 -SH Hydrophobic Molecules J.Am.Chem.Soc. 1998 , 120 , 6603 Silica Enantioselective Antibody Chiral Drug Science , 2002 , 296 , 2198 Gold DNA Complementary DNA Science , submitted.
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 07/03/2008 for the course CHM 2046 taught by Professor Veige/martin during the Spring '07 term at University of Florida.

Page1 / 42

NanoLect4 - Protein Channels Nature's Quintessential...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online